installing Acrobat Pro DC exit code 7 error 1624

Win 7 - 64 bit - CC-member,  getting this repeating error message:

Exit Code: 7

Please see specific errors below for troubleshooting. For example, ERROR:

-------------------------------------- Summary --------------------------------------

- 0 fatal error(s), 1 error(s)

---------- Payload: Adobe Acrobat DC 15.7.20033.0 Adobe Acrobat\Setup.exe_15.007.20033 -----------

ERROR: Third party payload installer Adobe Acrobat\Setup.exe failed with exit code: 1624

-------------------------------------------------------------------------------------

I have tried installing with firewall and spyware turned off. I have uninstalled Acrobat XI. Lastly I have installed Acrobat Reader DC. Reader is functioning OK.

best wishes Martin.